The major source of starchy carbohydrate foods on a global basis is derived from grains (Gramineae). While there are other important starchy carbohydrate sources, such as potatoes, cassava, sweet potatoes etc., grains are pre-eminent in providing starchy carbohydrate energy for the world's population. One reason for this is that grains are harvested in a naturally dry state and hence are relatively non-perishable. By contrast potatoes, cassava and sweet potatoes, for example, are harvested at an elevated moisture content and because of this they have a shorter storage life in their harvested state.
Of the major food grains, wheat is produced in the largest tonnage. Rice and corn are produced in very large quantities, with barley, rye, sorghum, oats, millets etc being produced in substantial but lesser amounts. Of those grains which are used directly for food for human consumption (as distinct from grains which are used for animal feeds) rice is the only major grain which is cooked (mostly as white rice and to some extent as brown rice) by the ultimate consumer predominantly in a whole-grain form. No doubt the reason for this is that rice may be cooked, for example, by boiling in water in a period of time which is conveniently short, for example 15-20 minutes. Other major grains such as wheat, corn, rye, sorghum, barley, are very slow (and hence inconvenient) to cook. As a consequence the major usage of these grains as food is in the form of flours, flakes or meals which are more conveniently consumed in various forms such as bakery products, porridge, pastas, etc.
There exists however, especially in the Middle East, a traditional food based on whole-grain wheat whereby the grain is consumed as a whole or cracked grain in the form of Bulgur (or Burghul). Bulgur is really a parboiled wheat product (analogous to parboiled rice). However, since whole-grain bulgur is fairly slow cooking, (45-60 minutes of cooking) the individual grains are usually cracked into small pieces so that the consumer can cook the bulgur in a more conveniently shorter time. Even so cracked bulgur requires cooking for 10-15 minutes then gently steaming for a similar period.